Rechargeable battery module having optimized current conduction

ABSTRACT

An accumulator module (10) having a housing (12) and at least one carrier (18) that is placed in the interior of the housing (12) and is fitted with a plurality of accumulator cells (14). Each accumulator cell (14) has two poles, an end-face contact (28) at a top of the accumulator cell (14) and a lateral surface (30) on a lateral side of the accumulator. A cell connector (16) is provided to conductively connect accumulator cells (14) of adjacent groups of accumulator cells (14). The cell connector (16) has an elongated body that conductively contacts the end-face contacts (28) of a plurality of accumulator cells (14) in one group to the lateral surfaces (30) of a plurality of other accumulator cells (14) in another group. The cell connector (16) comprises contact tongues (46) for contacting the end-face contacts (28) and contact lugs (48) for contacting the lateral surfaces (30).

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates in general to a device, basically known per se,for storing electrical energy and for contacting energy storage cellsincluded in the device, i.e., a device that functions as an energy store(energy storage device).

Description of Related Art

DE 10 2012 213 273 A1 describes an energy storage device for a vehicle.Energy storage devices are generally used for a mobile power supply, foran emergency power supply, and the like.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an energy storagedevice, referred to below as an accumulator module, having optimizedcurrent conduction for accumulator cells included in the accumulatormodule.

In summary, the invention proposes a novel type of current conduction inaccumulator units, referred to below as accumulator cells (the so-calledsecondary cells that function as energy storage cells), in particularaccumulator cells in the form of round cells, and in one particularembodiment, optionally combinable therewith, a novel way of efficientlydissipating heat from an accumulator cell included in the accumulatormodule, in particular an accumulator cell in the form of a round cell,or a group of such accumulator cells.

This is achieved in that the cell contacting, namely, electricallyconductive cell contacting for the current conduction from and/or to theparticular accumulator cell, takes place solely from one side. Theopposite side, for example and in principle optionally, is thereforeavailable strictly for heat dissipation. The heat may thus betransported on or to a cooling surface or the like over the shortestpath. The accumulator cells are held in position by a cell holder thatfunctions as a carrier.

The above-mentioned object is achieved according to the invention bymeans of an accumulator module that functions as an energy storagedevice, having the features of claim 1. In such an accumulator module,at least one carrier that is providable with a plurality of accumulatorcells is placeable in the interior of a housing of the accumulatormodule, and in an operationally ready accumulator module, at least onecarrier that is provided with a plurality of accumulator cells is placedin the interior of the housing of the accumulator module. Theaccumulator module includes contacting means for electrical contactingof the accumulator cells solely from one side for conducting currentfrom and to an accumulator cell or between accumulator cells of a groupof accumulator cells.

The special feature of the accumulator module proposed here lies in thefact that the accumulator cells are contacted solely from one side. Asis known, it is common for accumulator cells, whose outer surfacesfunction as poles, to be contacted at both ends, and for accumulatorcells in the form of round cells, for example, to be contacted at bothof their end sides/end faces. The electrical contacting of theaccumulator cells solely from one side proposed here, sometimes alsoreferred to below only as “one-side contacting” for short, allows aparticularly space-saving shape of the electrically conductiveconnection of a plurality of accumulator cells, and since provision ofconductor tracks from one end of an accumulator cell to the area of theopposite end is not necessary, also allows a high packing density of aplurality of accumulator cells, which according to the approach proposedhere are combined in an accumulator module. Lastly, the short conductorpaths and few material transitions result in only minor power loss. Theone-side contacting thus represents optimized current conduction withinthe accumulator module and between the accumulator cells includedtherein, as well as their outer surfaces that function as poles.

The one-side contacting does not necessarily refer just to a singlegeometric outer surface of the accumulator cell/round cell in question.Rather, the one-side contacting refers to one of the oppositely situatedends of the accumulator cell/round cell in question along a longitudinalaxis of the accumulator cell/round cell. For a cylindrical accumulatorcell (round cell) or an accumulator cell having the geometric shape of aregular cylinder, the one-side contacting in principle may thus belimited to the cover surface or base surface of the round cell, in that,for example, concentric sections of the cover surface or base surfacefunction as poles. However, the one-side contacting may also refer tothe cover surface or base surface as well as a section of thecylindrical surface on the cover side or the base side, in that on theone hand a section of the cover surface or base surface, and on theother hand a cover-side or base-side section of the circumferentialsurface, function as poles. A cover-side section of the circumferentialsurface of an accumulator cell is a surface section that adjoins thecover surface; correspondingly, a base-side section of thecircumferential surface of an accumulator cell is a surface section thatadjoins the base surface. However, contacting of the cover surface onthe one hand and of the base surface on the other hand is not one-sidecontacting. Similarly, contacting of the cover surface and of abase-side section of the circumferential surface or contacting of thebase surface and of a cover-side section of the circumferential surfaceis not one-side contacting.

Advantageous embodiments of the invention are the subject matter of thesubclaims. Back-references that are used within the claims refer to thefurther development of the subject matter of the referenced claim by thefeatures of the respective dependent claim. They are not to be construedas a waiver of the attainment of independent subject matter protectionfor the features or feature combinations of a dependent claim.Furthermore, with regard to an interpretation of the claims and aninterpretation of the description, in the event of a more precisespecification of a feature in a dependent claim, it is to be assumedthat there is no such limitation in the respective preceding claims orin a more general embodiment of the accumulator module in question.Accordingly, any reference in the description to aspects of dependentclaims, even without being specifically mentioned, is also to beexplicitly construed as a description of optional features. Furthermore,it is pointed out that the claims filed with the present patentapplication are proposed formulations without prejudice to theattainment of further patent protection. Since in particular thefeatures of the dependent claims, with regard to the prior art on thedate of priority, may form separate, independent inventions, theapplicant reserves the right to make these or even further featurecombinations, heretofore disclosed only in the description and/ordrawings, the subject matter of independent claims or declarations ofdivision. Moreover, the features of the dependent claims may alsoinclude separate inventions that are independent from the subject matterof the respective referenced claims.

In one embodiment of the accumulator module, special electricallyconductive cell connectors function as contacting means for strictlyone-side electrical contacting of the accumulator cells, and on the onehand contact an end face-side contact, in particular a center contact,of at least one accumulator cell, or contact the end face-side contacts,in particular the center contacts, of all accumulator cells of a groupof accumulator cells, and on the other hand contact a circumferentialsurface of at least one accumulator cell or the circumferential surfacesof all accumulator cells of a group of accumulator cells. This is onepossible embodiment, and in the approach proposed here is the preferredembodiment, for electrically contacting the accumulator cells from onlyone side, with detachability in particular without tools. The contactingtakes place from the cover surface of an accumulator cell/round cell andan end face-side contact, present there, to a side surface of anotheraccumulator cell/round cell, or conversely.

The description is continued below, based on center contacts as endface-side contacts of the accumulator cells. Any time that a centercontact is mentioned, this is nevertheless always to be construed as themore general specification as an end face-side contact.

In another embodiment of an accumulator module according to theinvention, each cell connector is characterized by an elongated shape,and along its longitudinal extension contacts the center contacts ofmultiple accumulator cells as well as the circumferential surfaces ofmultiple further accumulator cells. In addition, such an elongated cellconnector has resilient contact tongues for contacting the centercontacts, and optionally likewise has resilient contact tabs forcontacting the circumferential surfaces of contact tabs. Due to theelongated shape, each cell connector can contact multiple accumulatorcells, namely, multiple accumulator cells in a row. Cross wiring, whichis necessary without such an elongated shape, is therefore dispensedwith. This saves space, results in a reduced number of materialtransitions and thus, reduced power loss, and lastly, simplifies theinstallation of an accumulator module. As a result of the resilientcontact tongues, tolerance compensation is provided, and secureelectrically conductive contacting of the accumulator cells, inparticular simultaneous secure electrically conductive contacting ofmultiple accumulator cells, is ensured.

In one special embodiment of the accumulator module according to theinvention, it is provided that each cell connector in a stepped profileincludes a horizontal section, at least one adjoining vertical or atleast essentially vertical section, optionally multiple verticalsections uniformly spaced along the longitudinal extension of the cellconnector, and at least one adjoining lateral section or multiplelateral sections that in each case adjoin a vertical section, and thatthe contact tongues are part of the horizontal section, and the contacttabs are part of the lateral section or the lateral sections. Due to thestepped profile, a cell connector on the one hand may contact aplurality of accumulator cells on their cover sides, and on the otherhand may contact a plurality of further accumulator cells on theircircumferential surfaces, so that the above-mentioned one-sidecontacting results for a plurality of accumulator cells.

In yet another embodiment of the accumulator module according to theinvention, the accumulator cells included therein have in theircircumferential surfaces a constriction in the form of a groove(elongated depression) that circumferentially extends completely or atleast in sections in the circumferential direction, and for electricallyconductive contacting of the accumulator cells, the contact tabs of thecell connectors engage with the constrictions in the accumulator cells.The contact tabs that engage with such constrictions are orientedtransversely or essentially transversely with respect to the centerlongitudinal axis of the accumulator cells. The contact tabs engagingwith the constrictions consequently fix the accumulator cells in theaxial direction. The contacting of the accumulator cells that resultsduring the engagement with the constrictions thus fulfills a doublefunction. On the one hand, secure electrically conductive contactingresults. On the other hand, mechanical contacting results, which bringsabout axial fixing of the accumulator cells.

In one embodiment of an accumulator module in which electricallyconductive contacting and axial fixing of the accumulator cells takeplace by means of contact tabs that engage with constrictions in thecircumferential surfaces of the accumulator cells, a/each accumulatorcell placed in the carrier is releasably lockable in the carrier via theor each contact tab that engages with the constriction. For thispurpose, each cell connector is connected to the carrier, at least insections, for example by fixing the cell connector in or on the carrier.The locking of an accumulator cell takes place via the engagement of atleast one contact tab with the constriction in the accumulator cell. Thelock may be released when the or each contact tab is disengaged from theconstriction.

In another embodiment of an accumulator module in which electricallyconductive contacting and axial fixing take place by means of contacttabs that engage with constrictions in the circumferential surfaces ofthe accumulator cells, a/each accumulator cell placed in the carrier isclampable by the two cell connectors by means of the or each contacttongue of a cell connector that contacts the center contact of theaccumulator cell, and by means of the or each contact tab of a furthercell connector that engage with the constriction, and in the insertedstate is clamped by the two cell connectors and the contact tongues orcontact tabs. As a result of this clamping, each accumulator cell isheld only, or at least essentially, by the cell connectors intended forthe electrically conductive contacting. A double function is thusprovided here as well, namely, electrically conductive contacting and atthe same time, mechanical retention of the accumulator cells.

In yet another embodiment of the accumulator module according to theinvention, the or each vertical or at least essentially vertical sectionof a cell connector functions as a spring element. Due to the steppedprofile mentioned above and fixing of the horizontal section, forexample in the form of fixing in or on the carrier, the or each verticalsection, and thus each cell connector, acts overall as a spring element.For a fixed horizontal section, the or each vertical section iselastically movable within the scope of the properties of the materialof the cell connector. Any electrical conductor is suitable as materialof the cell connector, for example copper or the like. Such materialsallow such elastic movability. The or each vertical section togetherwith the adjoining lateral section is thus resiliently elasticallymovable, and this elastic movability likewise ensures secureelectrically conductive contacting of the accumulator cells, inparticular simultaneous secure electrically conductive contacting ofmultiple accumulator cells.

In one special embodiment of the accumulator module, the carrierincludes as an integral component the cell connectors intended for theelectrically conductive contacting of the accumulator cells that areplaceable in the carrier, for example by extrusion-coating the cellconnectors with the material of the carrier (plastic) during manufactureof the carrier. The cell connectors are then integrated into the carrierin a vibration-resistant manner. Such a carrier (hybrid part) simplifiesthe installation of an accumulator module significantly. The carrier iscreated in one production step, and it is lastly necessary only toprovide it with accumulator cells. The provision may even be automated,and may take place in the form of simultaneously providing multiple orall accumulator cells. The electrically conductive connection andmechanical retention of the accumulator cell in the carrier is completedonly with the placement of an accumulator cell in such a carrier.Further steps for the electrically conductive contacting or for themechanical retention are not necessary. By means of the cell connectorsincluded in the carrier, high currents may be transmitted withpractically no loss, and may be adapted to the particular needs by theselection of the material of the cell connectors and/or the selection ofthe material thickness of the cell connectors.

In another embodiment of the accumulator module according to theinvention, the carrier has a circumferential edge, and has uniformlyspaced journals on a surface bordered by the edge, wherein a group ofjournals or a section of the edge together with at least one journaldefines insertion slots for placement in each case of an accumulatorcell in the carrier. The defined insertion slots ensure that a/eachaccumulator cell placed in the carrier occupies a position in which atleast secure electrically conductive contacting, in particular secureelectrically conductive contacting and secure mechanical retention,is/are ensured. In addition, the edge and/or the journals function(s) asa guide when an accumulator cell is placed in the carrier or multipleaccumulator cells are simultaneously placed in the carrier. For acarrier that is installed vertically or essentially vertically in theaccumulator module, the edge and the journals also function as supportsurfaces for the accumulator cells.

Lastly, in one preferred, optional embodiment of the accumulator moduleaccording to the invention it is provided that at least one carrierequipped with accumulator cells is placeable in the interior of thehousing of the accumulator module in a form that thermally couples thefree end faces of the accumulator cells to the housing, so that thethermal energy that results during operation may be dissipated via thehousing.

One exemplary embodiment of the invention is explained in greater detailbelow with reference to the drawings. Corresponding objects or elementsare provided with the same reference numerals in all figures.

The exemplary embodiment is not to be construed as limiting to theinvention. For example, instead of the round cells shown in theexemplary embodiment, energy storage cells having some other basicgeometric shape, for example cuboidal energy storage cells, aresuitable, and other possible basic geometric shapes may similarly beconstrued in each case. In addition, within the scope of the presentdisclosure, enhancements and modifications are also possible, inparticular those that are apparent to those skilled in the art withregard to achieving the object of the invention, for example bycombining or modifying individual features or method steps generally orspecifically described in connection with the description section andcontained in the claims and/or the drawings, and that by use ofcombinable features result in new subject matter or new method steps ormethod step sequences.

BRIEF DESCRIPTION OF THE DRAWINGS

In the figures,

FIG. 1 shows an accumulator module,

FIG. 2 shows a partially exploded illustration of an accumulator module,

FIGS. 3, 4, and 5 show a carrier for an accumulator module according toFIG. 2, which is intended for accommodating a plurality of accumulatorcells,

FIGS. 6, 7, and 8 show one-side electrically conductive contacting,proposed herein, of the accumulator cells in a carrier intended foraccommodating same,

FIG. 9 shows a cell connector that is provided for such one-sidecontacting, in different views,

FIG. 10 shows two accumulator cells that are electroconductivelyconnected by means of a cell connector according to FIG. 9,

FIGS. 11 and 12 show the carrier in a view from above, with the cellconnectors embedded therein,

FIG. 13 shows the entirety of all cell connectors embedded in a carrier,without the surrounding carrier,

FIG. 14 shows a carrier that is fully equipped with accumulator cells,in a top view,

FIG. 15 shows an electrical equivalent circuit diagram for the fullyequipped carrier according to FIG. 14,

FIG. 16 shows an illustration for showing heat transfer from theaccumulator cells to a housing of the accumulator module, and

FIG. 17 shows a detail of an illustration with accumulator cell endfaces resting against the inner surface of a side wall of the housing ofthe accumulator module.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The illustration in FIG. 1 (FIGS. 1A, 1B, 1C) schematically shows in asimplified manner an accumulator module 10 that functions as an energystorage device. An accumulator module 10 according to FIG. 1A may beused alone as a current or voltage source (only the property of theaccumulator module 10 as a voltage source is discussed below, asnecessary; of course, a function as a current source or in general as anenergy source is to construed in each case).

The special feature of an accumulator module 10 of the type proposedhere lies in its modularity, as described in the parallel filed U.S.patent application Ser. No. 16/310,815 (internal reference 124 002 P WO,entitled: “Accumulator module”), which is to be incorporated in fullinto the present description to avoid unnecessary repetitions of thiscited reference.

An accumulator module 10 according to FIG. 1A may, for example, becombined with an accumulator module 10 according to FIG. 1B or with anaccumulator module 10 according to FIG. 1C. The accumulator modules 10are arranged in succession in a train-like manner in such a way that arear side surface of one accumulator module 10 faces a front sidesurface of an accumulator module 10 that follows in the resulting train.In such a combination, the accumulator module 10 according to FIG. 1Aforms the termination of a resulting train. The number of precedingaccumulator modules 10 in the train either according to FIG. 1B oralternatively according to FIG. 1C is in principle arbitrary. Whenmultiple accumulator modules 10 according to FIG. 1B are interconnectedto a terminating accumulator module 10 according to FIG. 1A, a parallelconnection is created, resulting in a current, tappable at the input ofthe train of the interconnected accumulator modules 10, that is equal tothe sum of the currents that are outputtable by the individualaccumulator modules 10. When multiple accumulator modules 10 accordingto FIG. 1C are interconnected with a terminating accumulator module 10according to FIG. 1A, a series connection is created, resulting in avoltage, tappable at the input of the train of the interconnectedaccumulator modules 10, that is equal to the sum of the individualvoltages of each accumulator module 10.

Each accumulator module 10 includes a housing 12 (FIG. 2) thataccommodates the accumulator cells 14 (FIG. 2). The illustration in FIG.2 shows a partially exploded illustration of one embodiment of anaccumulator module 10 according to the invention. A section of a trainprofile functions as a housing 12 or at least essentially as a housingelement. Four side surfaces of the housing 12 enclose a cavity thataccommodates the accumulator cells 14. The open sides of the housing 12are closed by (front and rear) side surfaces, not shown here, thatfunction as the front side and the rear side of the accumulator module10. In an accumulator module 10 according to FIG. 1A, the terminals ofthe accumulator module 10 are led toward the front side. In anaccumulator module 10 according to FIG. 1B or according to FIG. 1C, theterminals of the accumulator module 10 are led on the one hand towardthe front side, and on the other hand toward the rear side.

FIG. 2 shows that a plurality of accumulator cells 14 are used andelectrically combined in an accumulator module 10 according to theinvention. The accumulator cells 14 are combined into two groups each ina matrix-like manner (next to and above one another, i.e., in in rowsand columns in a manner of speaking). The number of accumulator cells 14combined in a row in such a group and the number of rows depend on theshape and size of the accumulator cells 14 as well as the internalvolume of the housing 12, but in principle are arbitrary. The dimensions(rows, columns) of both groups within an accumulator module 10 arepreferably identical.

The accumulator cells 14 are electroconductively contacted by means ofcontact elements that function as cell connectors 16. A carrier 18accommodates the accumulator cells 14 and the cell connectors 16. Thecarrier 18 accommodates the cell connectors 16 in that the material ofthe carrier 18 surrounds the cell connectors 16 in sections. The carrier18 is a hybrid part, and includes the cell connectors 16 as an integralcomponent. The carrier 18 accommodates the accumulator cells 14 ininsertion slots provided for this purpose. The carrier 18 holds (in thesense of fixing) the individual accumulator cells 14 in the positionsspecified by the insertion slots, and fixes them in their axialorientation. Situated between two equipped carriers 18 that are placedin the housing 12 is a central unit (not shown), for example a centralunit that includes a battery management system basically known per se, acurrent measuring section, a switchable relay, and/or a safety fuse, andthat exits from the outwardly led terminal contacts.

A carrier 18 equipped with accumulator cells 14 is shown in theillustration in FIG. 3. For clarification of the placement of anaccumulator cell 14 in its insertion slot in the carrier 18, anaccumulator cell 14 is shown above the carrier 18 and above theinsertion slot provided to accommodate it. The accumulator cell 14 isinserted into the carrier 18 by moving it along the direction depictedby the block arrow in FIG. 3, and is placed in the free insertion slotin the carrier 18.

The illustration in FIG. 4 shows on the one hand the carrier 18 (withthe cell connectors 16 integrally connected thereto), and on the otherhand, above the carrier 18, the accumulator cells 14 intended forplacement in the carrier 18. Further details of the carrier 18 areapparent from the illustration in FIG. 4. The carrier 18 has an outercircumferential edge 20, and uniformly spaced dome-like journals 22 inthe area bordered by the edge 20. Each journal 22 has four concavesurface sections that are uniformly spaced in the circumferentialdirection of the journal 22, namely, surface sections of a cylindershell. The radius of these surface sections corresponds essentially tothe radius of an accumulator cell 14 designed as a round cell. It isapparent in the illustration that a plurality of journals 22 aresituated next to one another in a matrix-like structure in the areabordered by the edge 20. The distance between the journals 22corresponds essentially to the diameter of an accumulator cell 14designed as a round cell. In each case a group of four journals 22 holds(in the sense of fixing) an accumulator cell 14 and fixes it in theaxial direction. The edge 20 includes a plurality of adjoining surfacesections that are concave in the direction of the journals 22, namely,surface sections of a cylinder shell. The radius of these surfacesections likewise corresponds essentially to the radius of anaccumulator cell 14 designed as a round cell. Such a surface sectiontogether with two adjacent journals 22 in each case holds (in the senseof fixing) an accumulator cell 14 and fixes it in the axial direction.At the four corners of the edge 20, this results in a concave surfacesection whose radius likewise corresponds essentially to the radius ofan accumulator cell 14 designed as a round cell. However, the arc lengthof this surface section is longer than the arc length of theabove-mentioned surface sections of the edge 20, and this surfacesection together with the one adjacent journal 22 in each case likewiseholds (in the sense of fixing) an accumulator cell 14 and fixes it inthe axial direction. When a variable (radius, diameter) has beenspecified by the term “essentially” in this paragraph, this isunderstood to mean that, for example, the radius of the surface sectionsof the journals 22 is slightly larger than the radius of the accumulatorcell 14, so that a form-fit surface fit is possible.

The illustration in FIG. 5 shows the carrier 18 according to FIGS. 3 and4 from a different perspective, and accumulator cells 14 placed therein.In this fully equipped configuration, in each case two carriers 18 arepushed into the housing 12 (FIG. 2), and in the state inserted into thehousing 12 are fixed in the housing 12 by means of at least one spacerpiece 24 (FIG. 2) that is insertable between the carriers 18 and thatfunctions as a spreading element, particularly preferably in such a waythat the free top sides/free end sides/free end faces of the accumulatorcells 14 inserted into the carriers 18 rest against the inner surface ofthe housing 12 for heat dissipation on the housing 12.

The carriers 18 are dimensioned in such a way that they fit exactly inthe housing 12. In the inserted state, the particular carrier 18 is thusalready fixed to some extent in the housing 12. For a housing 12according to FIG. 2, i.e., a housing 12 having an inwardly pointing Tprofile, the T profile determines a minimum distance between thecarriers 18, and the spacer pieces 24 are each pushed beneath a leg ofthe T profile, and thus between the T profile and the respectiveadjoining carrier 18. The spacer pieces 24 are guided through the Tprofile during insertion. The spacer pieces 24 have a slightly wedgedshape; i.e., they increase in their effective width (effective in thespreading direction) along their longitudinal axis, and thus cause adisplacement of the particular carrier 18 in the direction of thenearest side surface of the housing 12, and ultimately, the fixing ofthe carrier 18 in the housing 12.

The illustration in FIG. 6 once again shows details of the electricalcontacting of the accumulator cells 14 inserted into a carrier 18.Portions of the journals 22 of the carrier 18 are also discerniblebetween the accumulator cells 14. For the electrical contacting of theaccumulator cells 14 proposed here, it is essential that insulation 26extends over only a portion of the overall height of the accumulatorcells 14.

It is known that battery cells 14 in a customary configuration as roundcells or the like are contacted at both ends (end faces), namely, on theone hand at a center contact 28 that protrudes beyond one of the two endfaces, and on the other hand, at the oppositely situated end face, theinsulation 26 being dispensed with at this opposite end face, so thatthe metallic casing, which as a whole represents the center contact 28that functions as a first contact, as well as the second contact of theaccumulator cell 14, is exposed. Instead of such contacting (contactingon both sides) which has been customary thus far, according to theapproach proposed here the contacting of the accumulator cells 14 takesplace solely from one side. Thus, the opposite side which heretofore haslikewise been contacted is available, for example and in principleoptionally, for heat dissipation.

The one-side contacting of the accumulator cells according to theapproach proposed herein is based on use of specially shaped cellconnectors 16, which on the one hand contact the center contact 28 of atleast one first accumulator cell 14, and on the other hand contact anarea, free of insulation 26, of the circumferential surface 30 of atleast one adjacent further accumulator cell 14. The contacting of aplurality of accumulator cells 14 thus proceeds from the cover surfaceof an accumulator cell 14 and the center contact 28 at that location, toa side surface of a further accumulator cell 14 and an area of thecircumferential surface 30 that is free of insulation 26 at thatlocation. The illustration in FIG. 6 shows this form of contacting,using three accumulator cells 14 as an example. Based on theillustration, it is readily conceivable that further accumulator cells14 may adjoin at the left and right of the three accumulator cells 14shown. In addition, it is likewise readily conceivable that accumulatorcells 14, which are contactable by means of an elongated cell connector16 extending transversely with respect to the plane of the drawing, maybe situated in front of and behind the three accumulator cells 14 shown.This results in the above-mentioned matrix-like arrangement of theaccumulator cells 14, which are all contacted from one side in thedescribed manner.

The illustration in FIG. 6 is a schematically simplified illustration ofthe basic principle of the one-side contacting of the accumulator cells14. The illustration shows one possible embodiment of the cellconnectors 16. The illustration in FIG. 7 shows one preferred specificembodiment of the cell connectors 16. In principle, each cell connector16 on the one hand contacts the center contact 28 of at least oneaccumulator cell 14, and on the other hand contacts the circumferentialsurface 30 of at least one adjacent accumulator cell 14. In theembodiment according to FIG. 7, the contacting of the circumferentialsurface 30 takes place in the area of a constriction 32 in thecircumferential surface 30. The end of the cell connector 16 providedfor contacting the circumferential surface 30 engages with thisconstriction 32, and this engagement brings about on the one hand secureelectrically conductive contacting of the particular accumulator cell14, and on the other hand also (locking) axial fixing of the particularaccumulator cell 14.

The illustration in FIG. 8 shows a side view of a group of accumulatorcells 14 as in FIG. 3 or FIG. 4, i.e., a group of accumulator cells 14that are placeable together in a carrier 18. It is pointed out that thegroup of accumulator cells 14 shown in FIG. 8 includes exactly sevenaccumulator cells 14. According to FIGS. 3 and 4, 7×10 accumulator cells14 are placeable in the carrier 18. The group shown in FIG. 8 is thusone of the group of seven in the carrier 18. Of course, for a carrier 18having larger or smaller dimensions, other numerical values arepossible, and the numerical values mentioned here as well as theillustrated numbers are strictly by way of example.

The accumulator cells 14 in a group according to FIG. 8 are connected toone another in the manner shown in FIG. 7; thus, the illustration inFIG. 7 may be understood as an enlarged detail of the illustration inFIG. 8. The electrically conductive connection of the group ofaccumulator cells 14 (further accumulator cells 14 are situatedtransversely with respect to the plane of the drawing, behind theaccumulator cells 14 shown) is completed by means of two special cellconnectors 16 that function as the first and the last cell connector 16,and that have end-position terminal tabs 36, 38 (first terminal tabs 36,second terminal tabs 38), already shown in the illustrations in FIGS. 2,3, and 4 but not identified in FIG. 2. These special cell connectors 16in each case contact only one row (group) of accumulator cells 14,namely, the special cell connector 16 shown at the right in FIG. 8, inthat it engages with the constriction 32 in the circumferential surfaces30 of the accumulator cells 14, and the special cell connector 16 shownat the left in FIG. 8, in that it contacts the center contacts 28 of theaccumulator cells 14. The above-described cell connectors 16 (FIG. 7)are situated between these two special cell connectors 16, and incontrast, in each case contact two (spatially) parallel, adjacent rows(groups) of accumulator cells 14. The first terminal tabs 36 are in eachcase directly or indirectly connected (via the central unit, forexample) to an outwardly guided terminal contact of the accumulatormodule 10. The second terminal tabs 38 are used for a series connectionof the carriers 18 and the accumulator cells 14 included in same.

The illustration in FIG. 9 (FIGS. 9A, 9B, 9C, and 9D) show such anelongated cell connector 16 in different views. The angular designalready shown in FIGS. 6, 7, and 8 and the stepped profile of the cellconnector 16 are apparent in particular in the top view of one of theend sides of the cell connector 16 in the illustration in FIG. 9D(viewing direction parallel to the longitudinal axis of the cellconnector 16). Accordingly, a cell connector 16 includes three sections,which for the purpose of simple terminology are referred to as thehorizontal section 40, the vertical section 42, and the lateral section44. By means of the horizontal section 40, the center contacts 28 arecontacted by accumulator cells 14 that are spatially aligned in a rowand combined into a group due to the spatial alignment in a row. Bymeans of the lateral section 44, the circumferential surfaces 30 arecontacted by the further accumulator cells 14 that are spatially alignedin a row in parallel and likewise combined into a group due to thespatial alignment in a row. The lateral section 44 may also beunderstood as a combination of multiple lateral sections 44 in a plane,each individual lateral section 44 being intended for contacting anaccumulator cell 14. In the embodiment shown (see in particular theillustrations in FIGS. 9A and 9B), each such lateral section 44 adjoinsa separate vertical section 42, so that the cell connector 16 in theembodiment shown encompasses, in one piece, the elongated horizontalsection 40 as well as multiple uniformly spaced vertical sections 42emanating therefrom, and lateral sections 44 that in each case adjoinsame. Each cell connector 16 is fixed in or on the carrier 18, forexample by injection-molding the horizontal section 40 of each cellconnector 16 with the material of the carrier 18 during its manufacture.

In the embodiment shown, the horizontal section 40 includes eightresilient, angled contact tongues 46 arranged in pairs and facing oneanother with their free end, wherein more or fewer contact tongues 46are also suitable in principle, and the arrangement in pairs representsonly one special embodiment. However, the embodiment shown, with contacttongues 46 oriented in parallel, is characterized by ease ofmanufacture. The free ends of the or each contact tongue 46 rest on acontacted center contact 28 of an accumulator cell 14, or the centercontact 28 of an accumulator cell 14 rests on the free ends of the oreach contact tongue 46. The plurality of contact tongues 46 ensuresthat, for example, if one or even multiple contact tongues 46 is/aredamaged, the remaining contact tongues 46 still establish a secureelectrically conductive connection. In addition, each individual contacttongue 46 resting against the contact 28 establishes electricallyconductive contact with the accumulator cell 14, resulting in aplurality of simultaneously effective contacts. This ensures secureelectrically conductive contacting of the center contact 28 with aslittle contact resistance as possible.

Each lateral section 44 ends in at least one contact tab 48. The contacttabs 48 are particularly clearly apparent in the illustration in FIG.9C, which shows a top view of the cell connector 16. In the embodimentshown, four contact tabs 48 oriented in parallel are provided forcontacting an accumulator cell 14 in each case, and together form agroup of contact tabs 48. More or fewer than four contact tabs 48 arelikewise possible in principle. It is apparent that the contact tabs 48that are in each case part of a group have different lengths. Two outer,long contact tabs 48 enclose two inner, shorter contact tabs 48. Theends of the contact tabs 48 of a group together describe a circular arc,and the radius of the circular arc corresponds to the radius of anaccumulator cell 14 designed as a round cell, or, within the meaning ofthe version described above, at least essentially corresponds to theradius of an accumulator cell 14 designed as a round cell.

In one embodiment according to FIG. 9, the cell connector 16 with thecontact tabs 48 engages with the constriction 32 of the circumferentialsurfaces 30 of the accumulator cells 14, and the mentioned circular arcshape ensures that each individual contact tab 48 engages with theconstriction 32. Here as well, the plurality of contact tabs 48 ensuresthat, for example, even if one or even multiple contact tabs 48 is/aredamaged, the remaining contact tabs 48 still establish a secureelectrically conductive connection. In addition, each individual contacttab 48 that engages with the constriction 32 and/or rests against thecircumferential surface 30 of the accumulator cell 14 establisheselectrically conductive contact with the accumulator cell 14, resultingin a plurality of simultaneously effective contacts. Here as well, thisensures secure electrically conductive contacting of the circumferentialsurface 30 of the accumulator cell 14 with as little contact resistanceas possible.

The engagement with the constriction 32 is made possible/facilitated bythe elastic deformability of the contact tabs 48 provided within thescope of the material properties of the cell connector 16. In addition,in one special embodiment the vertical section 42 also acts as a springelement with its elastic deformability provided within the scope of thematerial properties of the cell connector 16. The cell connector 16 ismade at least of an electrically conductive material, for example copperor copper alloys. When an accumulator cell 14 is inserted into thecarrier 18, the contact tabs 48 initially come into contact with thegeneral circumferential surface 30 of the accumulator cell 14. Bybending over the contact tabs 48 and/or bending back the verticalsection 42 in the direction toward the horizontal section 40, thecontact tabs 48 may yield and slide along the circumferential surface 30of the accumulator cell 14 upon further insertion of the accumulatorcell 14 into the carrier 18. Upon even further insertion of theaccumulator cell 14 into the carrier 18, the contact tabs 48 ultimatelyreach the area of the constriction 32 and submerge into same. This isshown in the illustration in FIG. 10, using the example of twoaccumulator cells 14 and a cell connector 16 that connects them. Duringinsertion of the accumulator cell 14 shown at the left in the axialdirection, the contact tabs 48 are bent over into the carrier 18 (notshown) in the insertion direction. The horizontal section 40 and thevertical section 42 of the cell connector 16 are fixedly connected tothe carrier 18, for example enclosed by the material of the carrier 18.For a corresponding axial position of the accumulator cell 14, the endsof the contact tabs 48 engage with the constriction 32. At that locationthe contact tabs 48 rest at least on an edge of the constriction 32 (inthe illustration, on the bottom edge of the constriction 32), whichresults in electrically conductive contact here with the circumferentialsurface 30 of the accumulator cell 14. The ends of the contact tabs 48also generally rest against a surface that borders the constriction 32(in the illustration, against the top horizontal surface bordering theconstriction 32). This results in further electrically conductivecontact here with the circumferential surface 30 of the accumulator cell14.

In the case of a resilient vertical section 42, this section springsback when the contact tabs 48 engage with the constriction 32.Regardless of an optional resilient property of the vertical section 42,an accumulator cell 14 on the one hand is securely electroconductivelycontacted by means of the contact tabs 48, and on the other hand isreleasably locked in the carrier 18 by means of the same contact tabs48. For removal of an accumulator cell 14 from the carrier 18, thesequence described above is reversed. During removal, it is firstnecessary to release the detent lock provided by the contact tabs 48,and for this purpose appropriate force must be applied to ensure that anaccumulator cell 14 that is locked in the carrier 18 does notinadvertently come out.

The height of a cell connector 16, which is determined by the length ofthe vertical section 42, together with the position of the constriction32 in the circumferential surface 30 of the accumulator cells 14, isselected in such a way that when the contact tabs 48 engage with theconstrictions 32 of a first row of accumulator cells 14, the contacttongues 46, under mechanical tension, rest on the center contacts 28 ofan adjoining second row of accumulator cells 14. In the inserted statein the carrier 18, each individual accumulator cell 14 is thus clamped,in a manner of speaking, between the contact tongues 46 of one cellconnector 16 and the contact tabs 48 of the neighboring cell connector16. This ensures not only the secure mechanical retention mentionedabove and the releasable locking in the carrier 18, but in particularalso secure, long-lasting electrically conductive contacting of eachaccumulator cell 14.

The two special cell connectors 16 mentioned above in conjunction withthe explanation of the illustration in FIG. 8 are basically cellconnectors 16 that are divided essentially along their longitudinalaxis, with lateral terminal tabs 36, 38. One of these special cellconnectors 16 (FIG. 8, right side) includes the contact tabs 48, or ingeneral, means for contacting a group of accumulator cells 14 at theircircumferential surfaces 30, in particular in constrictions 32 in thecircumferential surfaces 30. The other special cell connector 16 (FIG.8, left side) includes the contact tongues 46, or in general, means forcontacting a group of accumulator cells 14 at their end faces, inparticular their center contacts 28.

The illustrations in FIGS. 11 and 12 (FIG. 12 as an enlarged detail ofFIG. 11) show the carrier 18 with the cell connectors 16 included bysame (embedded therein) in a top view. The circumferential edge 20 aswell as the uniformly spaced journals 22 are apparent. The contacttongues 46 and the contact tabs 48 of the cell connectors 16 areapparent at the base of the channels, which remain between the journals22 or between the journals 22 and the edge 20, for accommodating anaccumulator cell 14 in each case (see in particular the enlargedillustration in FIG. 12). The curly brackets in the lower area of theillustration in FIG. 12 denote the width of a respective cell connector16, so that it is clear that a cell connector 16 on the one hand coversthe holding positions, situated in a row, for an accumulator cell 14 ineach case in the carrier 18, and on the other hand extends to theholding positions of a neighboring row in the carrier 18.

FIG. 13 shows once more (as in FIG. 2) the entirety of the cellconnectors 16 that are part of a carrier 18, together with the outerspecial cell connectors 16 and their terminal tabs 36, 38 as well as thecell connectors 16 that are enclosed by the special cell connectors 16.It is apparent that the cell connectors 16 that are part of a carrier 18are uniformly spaced and oriented in parallel to one another.

Lastly, FIGS. 14 and 15 respectively show a carrier 18 that is fullyequipped with accumulator cells 14, and the circuit diagram of such acarrier 18, with the accumulator cells 14 included by same, illustratedby the corresponding circuit symbols, and the interconnection of theaccumulator cells 14 that results due to the cell connectors 16. Here aswell, analogously to the illustration in FIG. 12, once again the areasof the cell connectors 16 are denoted by curly brackets. To the right ofthe circuit diagram, the text “1×V_(R),” “2×V_(R),” etc., indicates thatthe voltage that is tappable at a fully equipped carrier 18 increaseswith each row of accumulator cells 14, where V_(R) denotes the voltagethat results across a row due to the parallel connection of multipleaccumulator cells 14 in such a row (in the present case, ten accumulatorcells 14 by way of example).

The description of the exemplary embodiment now turns to the aspect ofheat dissipation. When the electrical energy stored in a galvanic cellis utilized, it is known that cell heating occurs due to the internalresistance. Increased or increasing ambient temperature acceleratesundesirable side reactions, and thus, the aging behavior of anaccumulator cell 14. This also applies for the accumulator cells 14 ofthe accumulator module 10 proposed herein. In addition, the speed of theself-discharge of an accumulator cell 14 is a function of thetemperature, among other factors. Therefore, efficient dissipation ofthe heat from the accumulator module 10 is meaningful. Conversely, lowambient temperatures, in particular temperatures below the freezingpoint of water, are similarly unfavorable, so that dissipation of heatfrom the accumulator module 10, and thus, an overalltemperature-dependent adjustment of the temperature of the accumulatormodule 10, are also meaningful.

It is apparent in the partially exploded illustration according to FIG.2 that the uncontacted end faces of the accumulator cells 14 placed ineach case in a carrier 18 face the inner side of a side surface of thehousing 12. Due to the one-side contacting of the accumulator cells 14described above, the end faces, opposite from the end faces with thecenter contact 28, of all accumulator cells 14 placed in a carrier 18are free and are available for efficient heat dissipation. These endfaces of the accumulator cells 14 are metallic, specific to the design,since these end faces in addition to the center contact 28 are generallyused as a second contact when an accumulator cell 14 is connected. Themetallic end faces also allow efficient heat transfer. The entirety ofthe metallic end faces of all accumulator cells 14 combined in a carrier18 is also particularly clearly apparent in the illustrations in FIGS.3, 4, and 5. It is also apparent that the stated end faces of allaccumulator cells 14 combined in a carrier 18 are in flush alignmentwith one another. All end faces thus lie in the same plane or at leastessentially in the same plane.

The heat transfer takes place in that all accumulator cells 14 placed ina carrier 18 rest with their above-mentioned end faces against the innerof a side surface of the housing 12, so that heat transfer to thehousing 12 occurs. Accordingly, heat conduction takes place in thematerial of the housing 12 according to physical laws, so that the outersurface of the housing 12 is heated. This heat, likewise according tophysical laws, is released to the surroundings by convection. The heatrelease may in principle be increased in a manner known per se byincreasing the effective surface of the housing 12, and accordingly thehousing 12 optionally has ribs or the like, in any casesurface-enlarging elements, on the outer surface of at least individualside surfaces.

The illustration in FIG. 16 is similar to the illustration in FIG. 6,except that depiction of the one-side contacting, which is the primaryfocus in the illustration in FIG. 6, has been omitted. However, theone-side contacting, in particular the one-side contacting according toFIG. 6, 7, or 8, is still present, so that reference is made to thepreceding description to avoid unnecessary repetitions.

The same as for the illustration in FIG. 6, multiple accumulator cells14 placed in a carrier 18 are shown. The accumulator cells 14 areaxially fixed in the carrier 18 or by means of the carrier 18, inparticular by means of the one-side contacting described above. Theaccumulator cells 14 are oriented in parallel to one another along theirlongitudinal axes. For a carrier 18 corresponding to the embodimentdescribed here, this parallel orientation of the accumulator cells 14,held on only one side, is achieved by long guiding by means of thejournals 22 and/or the edge 20 of the carrier 18. Long guiding refers tothe fact that the effective length of the journals 22 and/or of the edge20, as the support surface, corresponds to at least approximatelyone-third of the length of the accumulator cells 14; an embodiment witha greater effective length is also possible.

The free ends of the accumulator cells 14 of the or a carrier 18,contacted from one side, protrude beyond the carrier 18, and the endfaces at that location all point in the same direction, namely, in thedirection toward an inner surface of a side wall of the housing 12. Theend faces are likewise parallel to one another and parallel to the innersurface of the housing 12. All end faces lie in one plane or at leastessentially in one plane. The accumulator cells 14 rest with these endfaces either directly against the inner surface of the housing 12, orindirectly against the inner surface of the housing 12, on an electricalinsulator 50 mounted flatly on the inner surface of the housing 12. Theinsulator 50 is optionally a highly thermally conductive insulator 50,for example an insulator 50 in the form of an acrylic film or a filmmade of aluminum oxide. Such a film is, for example, a film having asmall thickness, for example a thickness of 0.2 mm to 0.3 mm.

In this form of heat transfer to the housing 12, electrically conductivecontacting of the type described above, namely, the one-side contactingby means of cell connectors 16 with resilient contact tongues 46 andlikewise resilient contact tabs 48, has proven to be particularlyadvantageous; accordingly, in one preferred embodiment it is providedthat for the heat transfer to the housing, the accumulator cells 14 aremechanically retained in the manner described above with an emphasis onthe electrical contacting. Namely, the mechanical retention by means ofthe contact tongues 46 and the contact tabs 48 ensures axial fixing ofthe accumulator cells 14 in the sense that each accumulator cell 14 issecurely held in the carrier 18 and is clamped, in a manner of speaking,by means of the contact tongues 46 and the contact tabs 48. Due to theresilient elasticity of the contact tongues 46 and the contact tabs 48,however, a certain axial movability is maintained. This axial movabilityapplies for each individual accumulator cell 14, and is presentindependently of all other accumulator cells 14 in the same carrier 18.This axial movability ensures that all free end faces of the accumulatorcells 14 placed in a carrier 18 rest against the inner surface of thehousing 12 or the insulator 50 mounted at that location. This ensuresthat each individual accumulator cell 14 takes part in the heat releaseto the housing 12.

For simplification, this situation may be considered as a plurality ofmutually parallel coil springs that are mounted on a shared base plateand oriented normal to the plane of the base plate in the longitudinaldirection. The base plate corresponds to the carrier 18 of theaccumulator module 10 according to the invention. Each coil springcorresponds to an accumulator cell 14 of the accumulator module 10according to the invention. The free ends of the coil springs correspondto the free ends of the accumulator cells 14. When an additional plateis pressed onto the free ends of the coil springs, at some point thisresults in a position, depending on the applied pressure, in which thefree ends of all coil springs are in contact with the additional plate.This is the situation in which the free end faces of the accumulatorcells 14 are in contact with the inner surface of the housing 12 or theinsulator 50 mounted thereon.

Thus, it is important to note that particularly efficient heat transferto the housing 12 is achievable when the accumulator cells 14 areresiliently supported, so that all accumulator cells 14 in a carrier 18are independently axially movable to some extent, although they arebasically axially fixed in the carrier 18. The contact tongues 46 andcontact tabs 48 are only one example, and represent one possibleembodiment of such resilient support.

FIG. 16 shows this resilient axial movability of the accumulator cells14 in the carrier 18 and relative to the carrier 18 by means of theblock arrows on both sides. The forked block arrows show the heattransfer from an accumulator cell 14 in each case to the housing 12, andillustrate that the thermal energy transferred into the housing 12 isdistributed at that location according to physical laws, so that,instead of the comparatively small end faces of the accumulator cells14, the significantly larger surface of the housing 12 or of arespective side surface of the housing 12 is effective for dissipatingheat from the accumulator cells 14. The block arrow shown next to thecarrier 18 and pointing in the direction of the housing 12, and theblock arrow shown next to the housing 12 and pointing in the directionof the carrier 18 and the accumulator cells 14 placed therein,illustrate that for maintaining the thermal contacting of the housing12, either the carrier 18 together with the accumulator cells 14 placedtherein is moved in the direction of the particular side wall of thehousing 12, or the housing 12 or its side wall is moved in the directionof the accumulator cells 14 placed in the carrier 18.

Such a movement of a carrier 18 together with the accumulator cells 14combined therein takes place by means of at least one spacer piece 24(FIG. 2), it being assumed in the embodiment shown in FIG. 2 that thehousing 12 accommodates two equipped carriers 18 in which the free endsof the accumulator cells 14 placed therein point in opposite directions.Accordingly, the or each spacer piece 24 is inserted between the twocarriers 18 after they have been simultaneously or successively placedin the housing 12. Inserting the or each spacer piece 24 between the twocarriers 18 increases the distance between the carriers 18 (function ofthe spacer piece 24 as a spreading element), so that the carriers arepressed by the or each spacer piece 24 in the direction of therespective opposite side surface of the housing 12. As a result of thisdisplacement, the free end faces of the accumulator cells 14 ultimatelycome into contact with the inner surface of the particular side wall ofthe housing 12 or an insulator 50 mounted at that location, and thedesired thermal contacting of the housing 12 is provided.

The illustration in FIG. 17 shows an enlarged detail of a portion of thehousing 12 according to FIG. 2, with the cooling ribs that areoptionally present on the outer surface of the housing 12, as well asindividual accumulator cells 14 that are pressed against the innersurface of the shown side wall of the housing 12 by means of a carrier18, being visible. The mentioned resilient axial movability of theaccumulator cells 14 is provided by the contact tongues 46 pressing ontothe center contact 28, and by the contact tabs 48 engaging with theconstriction 32.

The heat release from the housing 12 to the surroundings may be furtherassisted by optional additional heat dissipation from the housing 12.For example, cooling by means of a fluid that flows through coolingchannels is suitable in this regard. The cooling channels extend atleast in the side walls of the housing 12 that are thermally contactedby the accumulator cells 14 and/or in cooling ribs optionally present atthat location, wherein a deflection of one cooling channel into asubsequent cooling channel takes place, for example, via a correspondingfront and rear side surface.

In addition to the heat dissipation of the accumulator cells 14described above, controlled heating of the accumulator cells 14 may alsotake place, for example at low temperatures and with accompanyingunfavorable aging behavior of the accumulator cells 14, when theaccumulator cells thermally contact the inner surface of a side surfaceof the housing 12 or an insulator 50 mounted at that location, in themanner described above. The housing 12 or the or each relevant sidesurface is then heated, for example electrically or by means of a heatedfluid that flows through cooling channels in the housing 12.

Although the invention has been illustrated and described in greaterdetail with reference to the exemplary embodiment, the invention is notlimited to the disclosed example(s), and other variations may be derivedtherefrom by those skilled in the art without departing from theprotective scope of the invention.

Individual key aspects of the description provided herein may thus bebriefly summarized as follows: The invention relates to an accumulatormodule 10 having optimized current conduction, namely, an accumulatormodule 10 having at least one carrier 18 that is placeable in theinterior of a housing 12 and providable with a plurality of accumulatorcells 14, and having contacting means 16, for example the cellconnectors 16 described herein, for electrical contacting of theaccumulator cells 14 from only one side for conducting current from andto an accumulator cell 14 or between accumulator cells 14 of a group ofaccumulator cells 14.

LIST OF REFERENCE NUMERALS

-   -   10 accumulator module    -   12 housing    -   14 accumulator cell    -   16 cell connector    -   18 carrier    -   20 edge (of the carrier)    -   22 journal (on the carrier)    -   24 spacer piece    -   26 insulation (of an accumulator cell)    -   28 end face-side contact/center contact (of an accumulator cell)    -   30 circumferential surface (of an accumulator cell)    -   32 constriction (in the circumferential surface of an        accumulator cell)    -   34 (not assigned)    -   36 terminal tab    -   38 terminal tab    -   40 horizontal section (on the cell connector)    -   42 vertical section (on the cell connector)    -   44 lateral section (on the cell connector)    -   46 contact tongue (on the cell connector)    -   48 contact tab (on the cell connector)    -   50 insulator

The invention claimed is:
 1. An accumulator module (10), comprising: ahousing (12); at least one carrier (18) that is placed in the interiorof the housing (12) and is fitted with a plurality of accumulator cells(14), wherein each accumulator cell (14) has a body with a top and alateral side, and comprises two poles including an end-face contact (28)at the top of the accumulator cell (14) and a lateral surface (30) atthe lateral side of the accumulator cell (14); and at least one cellconnector (16) electrically conductively contacting the accumulatorcells (14) to carry current between accumulator cells (14) of adjacentgroups of accumulator cells (14), wherein: the cell connector (16) hasan elongated body that electrically conductively contacts the end-facecontacts (28) of a plurality of accumulator cells (14) in a first groupto the lateral surfaces (30) of a plurality of other accumulator cells(14) in a second group, and the cell connector (16) comprises aplurality of contact sections (40, 42, 44) each comprising at least onecontact tongue (46) contacting the end-face contact (28) of acorresponding accumulator cell (14) in the first group and at least onecontact tab (48) contacting the lateral surface (30) of a correspondingaccumulator cell (14) in the second group, the plurality of contactsections (40, 42, 44) of the cell connector (16), each including thetongue (46) and the contact tab (48), are in one piece, and eachaccumulator cells (14) in the first group is conductively contacted bytwo, separate, cell connectors (16), and wherein the end-face contact(28) of each accumulator cell (14) in the first group is conductivelycontacted by a corresponding contact tongue (46) of one of the two cellconnectors (16), and the lateral surface (30) of each accumulator cell(14) in the same first group is conductively contacted by acorresponding contact tab (48) of another one of the two cell connectors(16).
 2. The accumulator module (10) according to claim 1, wherein, in astepped profile, each contact section of the cell connector (16) has ahorizontal portion (40), an adjoining vertical or at least essentiallyvertical portion (42) and a lateral portion (44) which in turn adjoinssaid vertical portion, and wherein the at least one contact tongue (46)is part of the horizontal portion (40) and the at least one contact tab(48) is part of the lateral portion (44).
 3. The accumulator module (10)according to claim 2, wherein each accumulator cell (14) has aconstriction (32) in the lateral surface (30) thereof, wherein the atleast one contact tab (48) engages in the constrictions (32) of theaccumulator cells (14) in order to electrically conductively contactsaid accumulator cell.
 4. The accumulator module (10) according to claim3, wherein an accumulator cell (14) placed in the carrier (18) can bereleasably latched in the carrier (18) by means of the at least onecontact tab (48) that engages in the constriction (32).
 5. Theaccumulator module (10) according to claim 3, wherein there are at leasttwo cell connectors (16), and wherein an accumulator cell (14) placed inthe carrier (18) can be clamped by the two cell connectors (16) by meansof the at least one contact tongue (46) of one cell connector (16) thatcontacts the end-face contact (28) of said accumulator cell (14), and bymeans of the at least one contact tab (48) of another cell connector(16) that engages in the constriction (32) of said accumulator cell(14).
 6. The accumulator module (10) according to claim 2, wherein thevertical or at least essentially vertical portion (42) of a cellconnector (16) acts as a spring element.
 7. The accumulator module (10)according to claim 1, wherein the carrier (18) has a peripheral edge(20) and journals (22) that are evenly spaced on a surface delimited bythe edge, and wherein a group of journals (22) or a portion of the edge(20) together with at least one journal (22) define slots for placing anaccumulator cell (14) in the carrier (18) in each case.
 8. Theaccumulator module (10) according to claim 1, wherein at least onecarrier (18) fitted with accumulator cells (14) can be placed in theinterior of the housing (12) in a form that thermally couples free endfaces of the accumulator cells (14) to the housing (12).
 9. Anelectrical device comprising at least one accumulator module (10)according to claim
 1. 10. The accumulator module (10) according to claim1, wherein the at least one contact tongue is resilient.
 11. Anaccumulator module (10), comprising: a housing (12); at least onecarrier (18) that is placed in the interior of the housing (12) and isfitted with a plurality of accumulator cells (14), wherein eachaccumulator cell (14) has a body with a top and a lateral side, andcomprises two poles including an end-face contact (28) at the top of theaccumulator cell (14) and a lateral surface (30) at the lateral side ofthe accumulator cell (14); and at least one cell connector (16)electrically conductively contacting the accumulator cells (14) to carrycurrent between accumulator cells (14) of adjacent groups of accumulatorcells (14), wherein: the cell connector (16) has an elongated body thatelectrically conductively contacts the end-face contacts (28) of aplurality of accumulator cells (14) in a first group to the lateralsurfaces (30) of a plurality of other accumulator cells (14) in a secondgroup, and the cell connector (16) comprises a plurality of contactsections (40, 42, 44) each comprising at least one contact tongue (46)contacting the end-face contact (28) of a corresponding accumulator cell(14) in the first group and at least one contact tab (48) contacting thelateral surface (30) of a corresponding accumulator cell (14) in thesecond group, each accumulator cells (14) in the first group isconductively contacted by two, separate, cell connectors (16), andwherein the end-face contact (28) of each accumulator cell (14) in thefirst group is conductively contacted by a corresponding contact tongue(46) of one of the two cell connectors (16), and the lateral surface(30) of each accumulator cell (14) in the same first group isconductively contacted by a corresponding contact tab (48) of anotherone of the two cell connectors (16), and the carrier (18) compriseschannels defining a base, and as an integral component, the cellconnector (16) intended for electrically conductively contacting theaccumulator cells (14) placed at the base of the channels in the carrier(18), wherein each accumulator cell (14) has a constriction (32) in thelateral surface (30) thereof, wherein the at least one contact tab (48)engages in the constriction (32) of the respective accumulator cells(14) in order to electrically conductively contact the respectiveaccumulator cell, and wherein the respective accumulator cells (14)placed in the carrier (18) can be releasably latched in the carrier (18)by means of the at least one contact tab (48) that engages in theconstriction (32).